AI can see through tree tops?

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I know that AI can't see us through bushes and smoke, but I'm not sure if the same happens for tree foliage. I've seen many times how AI shoots us from a side of a valley to the other side, and we can't see them as they are behind the foliage of the trees in the forest.

Anyone can share more info, deny or confirm this?

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I know that AI can't see us through bushes and smoke, but I'm not sure if the same happens for tree foliage. I've seen many times how AI shoots us from a side of a valley to the other side, and we can't see them as they are behind the foliage of the trees in the forest.

Anyone can share more info, deny or confirm this?

From what I seen at nearly 1200 hours playing arma. ai can see through smoke and trees and pretty much foliage except the tall elephant grass.

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From what I seen at nearly 1200 hours playing arma. ai can see through smoke and trees and pretty much foliage except the tall elephant grass.

Except they can't see through the foliage. You can test this by placing yourself behind bushes and shooting at an enemy through them, and find that they will react slower to being shot at. If they start shooting in your direction, they're generally just estimating your whereabouts. Maybe there are some broken bushes, and I can't confirm your hunch with the elephant grass, because I've seen my AI shoot at enemies through that before, and I've also been shot hiding behind it.

In almost any case, though, this was because another enemy somewhere else saw me there and spotted me for his friends. At least that is what I suspect has happened. The AI's behaviour really is a black box, and what we perceive isn't necessarily what's actually happening. Devs say the AI cannot see through bushes, and strict testing regimes (individual bush, two AI only, that kind of thing, many tests over and over until you have something of statistical significance going on) support this, so I am more inclined to believe them than my own biases and my perception of what is happening around me.

Your perspective is limited to what you see at the moment you got shot, and not what the AI engine behind the scenes "saw". Something to keep in mind.

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From what I seen at nearly 1200 hours playing arma. ai can see through smoke and trees and pretty much foliage except the tall elephant grass.

Pictorial Evidence. Setup was as follows: Single AI standing with face towards me in a field, me in a row of bushes and trees. I run through a gap in the bushes, he immediately spots me and starts firing. Looses me behind the bushes, and even as I am firing past his head from behind one of the bushes, he doesn't shoot at me but towards the location where he lost sight of me.

View from my firing position (He his prone left side to the crosshair pipper)

View from his position with indicators

I'm gonna fool around with tree tops and the like a bit and see if I can find anything. Some bushes also work better than others, and at certain ranges bushes are completely ineffective (When firing from within 20 ish meters I was shot back at immediately.)

Edit: Turns out that firing two or more shots allows the AI to accurately pinpoint the location of the shots. Some bushes also do not offer total concealment, which allows the AI to spot you if you hide behind them for too long (unless you are prone.) if they have their attention focused in your direction. If they are locked on to you, moving from position to position can cause small slippages from concealment raise the AI's knowledge of you far enough to place accurate shots. How and if you are spotted hugely depends on the direction the AI is looking at the time too, it seems. So, the situation appears to be more complicated than "they can't see through bushes and foliage" vs "they can see through bushes and foliage".

//AI detection test by Greenfist 2015-09-12 v5Extract to user made missions folder and open with the editor.

White icons = He hasn't seen you at all.Blue= You're seen/heard but AI doesn't know if you're a friend or foe. Suspicious.

Yellow = AI knows you're an enemy, but haven't seen you yet.Green= You're recognized and seen but not currently visible.Red= The AI sees or hears you.The arrow shows the position where the AI thinks you are.

Actions:Look at me: Turns the enemy units towards you. (Only works when you're not yet detected )Move AI: Fly the AI unit around like a kite with your Jedi forces. (Usefull for checking the view blocking of objects.)Teleport enemy: moves enemy to cursor position.Teleport player: moves player to cursor position.Reset enemy: enemies forget about you and turn the other way.Get down/up: forces the enemy's stance to prone/standing.Splendid cam: it's splendid, isn't it?Enemy cam: Shows the view from enemy's eyes for a few seconds.

Shift + Left-clicking on the map: creates a move waypoint for the enemyAlt + click: teleport player

There's also small display on the bottom left corner with some vital info about the enemy.

To move this script to another map:Copy this init.sqf and GF_fncs.sqf to your mission folder.Preview.

You can edit it/change the units but the main villain should be named 'enemy1' and on EAST side. Script will create a basic OPFOR rifleman if enemy1 doesn't exist.

You can insert multiple units. Preferably in the same group as enemy1.

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AI cannot see though the main density of tree canopy or bush but the view block shape is smaller than the outer branches/leaves (to simulate seeing though leaves etc) The problem is that at the edges of the viewblock they can see perfectly but us humans still have to see through the leaves and branches so we have a major disadvantage.

The other problem of course is the AI seeing 'through' the ground. If you are prone on a rise above an AI he will spot you LONG before you can see them. This is of course because the grass only blocks your vision but also the AI is using low poly terrain to determine line of sight so you would appear floating slightly above the ground. (You can see the effect with terrain set to 'Very Low' and observing the distance.

I wish BIS could fix these problems because they are a major annoyance when fighting AI.

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There is an AI feature that can explain some cases of shooting through foliage: AI doesn't lose knowledge about enemy immediately after it broke LOS. I believe that knowledge decreases gradually over a certain amount of time.

Suppose there is an OPFOR tank, BLUFOR player and a small hill between them. Player moves on top of the hill and gets spotted by tank, tank's gunner rotates turret towards the player. If player hides on the slope of the hill, tank will still aim towards player through the hill and in some cases will follow player's movements with its turret for some time, even though nobody from tank's crew can see player. And here's the trick: if player instantly teleports behind the tank, its crew will be aware of player's completely new position, instantly rotate turret 180 degrees and aim exactly at him.

Maybe something like this applies to the forests too â€” even though players are hidden by tree cops, AI still retains the knowledge about them for some time and continues to engage. Players obviously try to return fire, that fire increases AI's knowledge about players, AI starts to make an accurate shots through trees creating an illusion that it can see through foliage.

One would assume with the new expansion being set in a jungle environment.that they're working on the AI as we speak.. And from dev updates looks to be the case.

In theory, AI couldn't see you trhough tree trunks, suppose it was a bug in recent builds. The lower LOS for cops could explain the issues, though I need to check then how the cops of near trees interpolate between them.

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@Greenfist: Awesome testing mission and tool that will be used extensively

Really nice. And it shows how stupid/ineffective the extrapolation/guesstimate of the AI is/can be. IMHO the AI should stop scanning/moving (or even turning in the opposite direction) once hitting "open area" but not seeing the target coming through there (guess that's hard to check for efficiently). This makes em look quite absurd at times (as shown here at ~1:20: the AI goes on scanning/watching out the sea, instead of pinpointing the target to a more feasible area).

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... AI doesn't lose knowledge about enemy immediately after it broke LOS. I believe that knowledge decreases gradually over a certain amount of time.

Suppose there is an OPFOR tank, BLUFOR player and a small hill between them. Player moves on top of the hill and gets spotted by tank, tank's gunner rotates turret towards the player. If player hides on the slope of the hill, tank will still aim towards player through the hill and in some cases will follow player's movements with its turret for some time, even though nobody from tank's crew can see player...

... Maybe something like this applies to the forests too â€” even though players are hidden by tree cops, AI still retains the knowledge about them for some time and continues to engage. Players obviously try to return fire, that fire increases AI's knowledge about players, AI starts to make an accurate shots through trees creating an illusion that it can see through foliage.

Not quite because the AI still have knowledge of your position, but rather it's extrapolation. Think about this: Say, you are in a forest, and through a gap you see a patrol walking to your right at 5 km/h. Your view to them is blocked by trees again now, but you'd like to flank them. Where would you go? You would kind of assume they'd keep their heading and speed, so you move right and forward, trying to get a look at them and find a good spot to set up an ambush.

AI's knowlege of location kind of acts similarly, and you can see this easily if you play as a subordinate, and with extended hud info enabled (Maybe wrong, not at my gaming computer now). Leader will tell you to engage a target and you see a red marker on it. Sometimes when it ran behind a cover and stayed, you can see that the marker continues to move past the cover.

(Another thing you might see is that if that enemy starts shooting from behind cover, the marker returns to him)

And here's the trick: if player instantly teleports behind the tank, its crew will be aware of player's completely new position, instantly rotate turret 180 degrees and aim exactly at him.

Hm. This is interesting... Though AI tank's spotting is a bit weird. I remember that if I crawl towards a tank from behind, I am fine. Not so if I stood and ran... Not entirely sure if this is the cause :(

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There is an AI feature that can explain some cases of shooting through foliage: AI doesn't lose knowledge about enemy immediately after it broke LOS. I believe that knowledge decreases gradually over a certain amount of time.

This is 2015. Please put this fairy tell to bed.

The only knowledge the AI retain is the target's speed and heading, so they have a chance of shooting you through a bush if you don't change direction or lie down. It also lets them use basic logic to anticipate where you might appear again.

As for the question, 'do AI see through tree tops?' No, they don't. Tree tops block AI vision.

But of course, there are no absolutes. This is like the question of, 'how long is Australia's coastline?' The answer is always different depending on how finely you measure, down to miles or micromillimeters.

Tree tops have an invisible blob-like shape that blocks AI vision, but since this isn't a perfect world and limitless processing power doesn't exist, the viewblock object doesn't correspond 100% to the thousands of little leaves that you see on the screen. So on the edges of tree canopies there will always be little disparities between what is visible to you AI vs humans.

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So on the edges of tree canopies there will always be little disparities between what is visible to you AI vs humans.

You not only have such disparities between AI and human vision, there are certainly also inter-human differences, and even a single entity on his own doesn't have constant vision (and cognitive) capacity. So that's not really a problem, actually it might be used to make the AI more human: by modeling vision that depends on other factors. Fatigue for example. Or combatMode. Observing/focusing on an area, or the environment as a whole is tiring and you can't do it constantly. Humans like to relax, even just for a bit.

IMHO a lot of the criticism does not have to do so much with actual vision capability of the AI, but rather with their reaction time or speed in doing so (detecting/locating you - while they were initially not paying much of attaintion for example...). So the problem is rather on the cognitive side of things. Sure, nobody wants to have "dumber" AI, but with respect to such cognitive capabilities there is certainly room for "improvement".

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Hey Greenfist. .. you still have the old mission for testing the ai seeing u in Grass kicking around... I meant to download it ages back but missed it...

Dude, that was almost a year ago, how can you even remember it was me? :)

Sorry, I don't have that mission anymore, but it was almost exactly the same as I linked here. You can use that with grass as well.

edit. Edited the test mission a bit. Nothing new, just a couple of tweaks.

Also, not sure if I saw it right, but while testing it looked like the AI's teammate shot at me through penetrable objects (bushes) if one of them spotted me, even if I was totally hidden from the shooter.

As in; I make eye contact with an enemy, fend him off while another one kills me from behind cover. This only happened right after when the group initially detected me. It's as if when the group learns of my position, the "trail" is still so fresh that even ones that don't see me might decide to take a shot.:confused:

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Dude, that was almost a year ago, how can you even remember it was me? :)

Sorry, I don't have that mission anymore, but it was almost exactly the same as I linked here. You can use that with grass as well.

edit. Edited the test mission a bit. Nothing new, just a couple of tweaks.

Also, not sure if I saw it right, but while testing it looked like the AI's teammate shot at me through penetrable objects (bushes) if one of them spotted me, even if I was totally hidden from the shooter.

As in; I make eye contact with an enemy, fend him off while another one kills me from behind cover. This only happened right after when the group initially detected me. It's as if when the group learns of my position, the "trail" is still so fresh that even ones that don't see me might decide to take a shot.:confused:

This could explain some of the claims of X-ray vision AIs.

LOL... yeah it was awhile ago... i gots one of those them elephant memory things going ons lol

Is the test mission still dev branch only?

1

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If you, as a player, observe an enemy move behind a tree or bush or rock, what do you do? Do you forget about them and stop firing? No; you suppress the hell out of the tree or bush or rock so that supporting units can close and destroy, even if you can't actually SEE the enemy. Can we please stop being mad at the AI for doing exactly what we would do?